Fundamental properties of solar-like oscillating stars from frequencies of minimum $Δν$ : II. Model computations for different chemical compositions and mass
类太阳恒星的振荡频率之间的巨大间隔是恒星平均密度的度量。在观测到的频率范围内，分离被认为是基本恒定的。然而，详细的研究表明，它们不是恒定的，它们的变化也不是随机的，而是对我们理解恒星结构和演化具有很强的诊断潜力。在这方面，最小大间隔的频率是非常有用的工具。从这些频率，除了大的分离和最大振幅的频率，Yıldız等人最近开发了新的方法来找到几乎所有的基本恒星属性。在本研究中，我们的目标是从频率中找到金属丰度和氦丰度，并将Yıldız等人给出的关系推广到更宽的恒星质量范围和任意金属丰度（$Z$）和氦丰度（$Y$）。我们发现，金属丰度的影响是{显着}的基本参数。例如，对于恒星质量，表达式必须乘以$(Z/Z_{\sun})^{0.12}$。对于任意氦丰度，$ M \propto (Y/Y_{\sun})^{0.25} $。从纯星震量确定$Z$和$Y$的方法是根据振荡频率间隔中振荡分量的振幅（\Dnu最大值和最小值之间的差异）。此外，我们证明了第一个最大值和第二个最小值之间的差异是非常敏感的$Z$。它还取决于$ν_{\rm min1}/ν_{\rm max}$和频率之间的小间隔。这种依赖性使我们开发了一种从振荡频率中找到$Z$（和$Y$）的方法。估计值和模型$Z$值之间的最大差异约为14%，而$Y$值为10%。
英文摘要：
The large separations between the oscillation frequencies of solar-like stars are measures of stellar mean density. The separations have been thought to be mostly constant in the observed range of frequencies. However, detailed investigation shows that they are not constant, and their variations are not random but have very strong diagnostic potential for our understanding of stellar structure and evolution. In this regard, frequencies of the minimum large separation are very useful tools. From these frequencies, in addition to the large separation and frequency of maximum amplitude, Yıldız et al. recently have developed new methods to find almost all the fundamental stellar properties. In the present study, we aim to find metallicity and helium abundances from the frequencies, and generalize the relations given by Yıldız et al. for a wider stellar mass range and arbitrary metallicity ($Z$) and helium abundance ($Y$). We show that the effect of metallicity is { significant} for most of the fundamental parameters. For stellar mass, for example, the expression must be multiplied by $(Z/Z_{\sun})^{0.12}$. For arbitrary helium abundance, $ M \propto (Y/Y_{\sun})^{0.25} $. Methods for determination of $Z$ and $Y$ from pure asteroseismic quantities are based on amplitudes (differences between maximum and minimum values of \Dnu) in the oscillatory component in the spacing of oscillation frequencies. Additionally, we demonstrate that the difference between the first maximum and the second minimum is very sensitive to $Z$. It also depends on $ν_{\rm min1}/ν_{\rm max}$ and small separation between the frequencies. Such a dependence leads us to develop a method to find $Z$ (and $Y$) from oscillation frequencies. The maximum difference between the estimated and model $Z$ values is about 14 per cent. It is 10 per cent for $Y$.
IZ Tel and UW Vir: Southern oscillating eclipsing Algol systems with active mass transfer
Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing, National Observatory of Athens（雅典国家天文台天文学、天体物理学、空间应用与遥感研究所）；The University of Queensland（昆士兰大学）；Astronomical Association of Queensland（昆士兰天文协会）；Çanakkale Onsekiz Mart University（恰纳卡莱18马月大学）
